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Drew Fustini
Drew Fustini
Drew Fustini is a hardware
designer and embedded Linux
developer. He is the Vice
President of the Open Source
Hardware Association, and a
board member of the
BeagleBoard.org Foundation.
Drew designs circuit boards for
OSH Park, a PCB manufacturing
service, and maintains the Adafruit
BeagleBone Python library.
ast time I was in Seattle, I
took a trip to the amazing
Living Computers Museum
to see a restored PDP-7, the
iconic minicomputer from
the mid-sixties that my
Twitter handle pays homage to. Only five
are known to have survived over the years,
of which two are functional. The one I went
to visit at the Living Computers Museum
has been restored to do something
extremely special: run UNIX Version 0.
Fifty years after Version 0, UNIX is
everywhere. It is the
root of the family
tree that gave us
macOS, Linux, and
the operating system
for every single
iPhone and Android
device. The impact
UNIX has had on
modern computing
is impossible to overstate, and it all started
with one borrowed PDP-7 at Bell Labs.
Bell Labs was the research division of
AT&T, the only phone company in the USA
at the time. AT&T’s monopoly meant that
Bell Labs had plenty of money for research,
leading to inventions including the transistor,
the laser, and the photovoltaic cell. It was
in this culture of innovation that a small
team of computer scientists, including
Ken Thompson and Dennis Ritchie, were
attempting to solve the big computing
problem of the day: time-sharing.
In those days, if you wanted a
computer to solve a problem, you hadto write instructions in assembly code,
put it onto punch cards, then hand those
cards to the computer operator to input
when the next batch processing slot was
available. Depending on how busy the
machine was, this could take hours, days,
or even weeks. Bell Labs was part of an
ambitious project named Multics that
aimed to create a time-sharing operating
system that could handle multiple users
at once.
Bell Labs eventually deemed Multics
a failure, which left Thompson and the
rest of the team
without direction or,
crucially, a computer.
Undeterred, they
found an unused
PDP-7 in another
department, who
were persuaded to
loan it out. In 1969,
Thompson’s family
went on a three-week vacation while he
wrote an assembler, a file editor, and a
kernel for the borrowed PDP-7. By the time
his family returned, Thompson had created
a multi-user time-sharing operating system:
UNIX Version 0.
There is so much more to this story:
the creation of the C programming
language, the beginning of the free
software movement, and the adventures of
Thompson’s pet crocodile. I’d recommend
the Command Line Heroes podcast
(hsmag.cc/PfhNL0), or you can make the
trip over to the Living Computers Museum
and see it for yourself!From the PDP-7
to your pocket
How UNIX took over the world
L
Only five are known to
have survived over the
years, of which two
are functional@pdp7